| 摘要 |
A cartridge has a one-piece reusable plastic casing that fits over a metal or plastic end cap and holds a bullet. The bullet end of the casing is provided with a ring or a plurality of rings or with a pronounced radially inward taper to engage corresponding surfaces on the bullet so that the bullet may snap into the casing. The bullet end of the casing is radially expansible to allow release of the bullet upon detonation of the powder in the cartridge. The plastic casing is provided with an end cap sealing flange generally being an axially thin, radially inwardly extending flange which fits snugly against the end cap of the cartridge. The flange is thick enough to withstand the high gas pressures upon firing of the powder, but is thin and flexible enough to elastically deform to produce a tight elastic seal against escape of the high-pressure gases around the end cap. The seal may be achieved, also with a thick, rigid flange and a compressible gasket. |
